The present invention relates to a mill of the type known from DE-OS No. 31 41 830 in which the seal consists of a compressible material in the form of an asbestos or ceramic cord. It has the object to seal the isolating air chamber of the mill to the outside in a gastight manner, and to prevent dust from escaping into the atmosphere. The seal is thereby in the position to absorb axial and radial movements, angular displacements, and a combination thereof. These movements can act on the parts coming into contact with one another. Furthermore, the seal has to absorb pressure surges of up to 1 bar and has to cause a reduction in noise. However, the asbestos or ceramic cord has the disadvantage that it hardens and thereby shrinks. In this manner, a gap can form between the cord and the adjacent parts so that leaks are created.